Device for limiting the speed of an engine

ABSTRACT

A wall and a flexible diaphragm are connected to provide a closed air chamber. An inlet is provided in the wall for supplying air having a pressure that is proportional to the speed of the engine. A compression spring engages the diaphragm to set the air pressure required in the air chamber to move the diaphragm. A link is attached to the diaphragm for limiting the engine speed in response to diaphragm movement.

United States Patent [72] Inventor James R. Graham Anderson, Ind. [21]Appl. No. 759,022 [22] Filed Sept. 11, 1968 [45] Patented Apr. 20, 1971[73] Assignee Pierce Governor Company, Inc. Upland, Ind.

[54] DEVICE FOR LIMITING THE SPEED OF AN ENGINE 8 Claims, 2 DrawingFigs.

[52] 11.8. CI 123/103, 92/ 1 3, 92/84 [51] Int. Cl ..F02d 1l/08, FOlb9/02,F16j1/10 [50] Field oIl'Search 123/103; 92/13; 92/84 [56]References Cited UNITED STATES PATENTS 2,215,406 9/1940 Paxman 92/84 I 2-I- HIGH LOW SPRING 30 AIR CHAMBER I5 AIR INLET I SPEED CHANGE ARM 34Primary Examiner-Mark M. Newman Attorney-Jeffers and Rickert ABSTRACT: Awall and a flexible diaphragm are connected to provide a closed airchamber. An inlet is provided in the wall for supplying air having apressure that is proportional to the speed of the engine. A compressionspring engages the diaphragm to set the air pressure required in the airchamber to move the diaphragm. A link is attached to the diaphragm forlimiting the engine speed in response to diaphragm movement.

AIR INTAKE 1 CARBURETOR DEVICE FOR LIMITING THE SPEED OF AN ENGINEBACKGROUND OF THE INVENTION My invention relates to a device forlimiting the speed of an engine, and particularly to such a device thatis operated by air pressure which varies as a function of the enginespeed.

Speed limiting devices or governors have been frequently provided forengines, particularly internal combustion engines for automobiles. Whilesuch governors have been satisfactory in some respects, such governorshave also had certain disadvantages. For example, such governors havebeen relatively complex devices, or have been relatively difficult toinstall. Both the complexity of the devices and the difficulty ofinstallation result in added cost.

Accordingly, a main object of my invention is to provide an improvedspeed limiting device or governor.

Another object of my invention is to provide an improved governor thatis relatively simple in structure, and that is relatively easy toinstall.

Another object of my invention is to provide an improved engine governorthat operates on air pressure that can be easily provided by an air pumpwhich can be positioned on the engine at a convenient point for power,and which can be easily connected to the governor by means of flexibletubing or hose.

Another object of my invention is to provide a relatively simple enginegovernor that can be conveniently mounted near the engine carburetor orelement to be controlled, and that can be easily and simply connected toa suitable air pump that supplies air whose pressure is proportional toengine speed.

SUMMARY OF THE INVENTION Briefly, these and other objects are achievedin accordance with my invention by a device comprising a wall and aflexible diaphragm that form a closed air chamber. An air inlet isprovided in the air chamber, and this inlet is adapted to be connectedto a pump that supplies air whose pressure varies as a function of thespeed of the engine. The device can be positioned near the desired speedcontrol element of the engine, such as the carburetor, and a link isconnected between the diaphragm and the speed control element. A springelement engages the flexible diaphragm and is arranged to urge thediaphragm into the air chamber. As the engine speed increases, the airpressure in the air chamber also increases until the diaphragm is movedoutward against the spring. This diaphragm movement is transferredthrough the link to the speed control element which then limits theengine speed. The spring element is preferably adjustable, so that theair pressure required to move the diaphragm may be set to limit theengine speed to the desired magnitude.

BRIEF DESCRIPTION OF THE DRAWING The subject matter which I regard as myinvention is particularly pointed out and distinctly claimed in theclaims. The structure and operation of my invention, together withfurther objects and advantages, may be better understood from thefollowing description given in connection with the accompanying drawing,in which:

FIG. I shows a side view, partly in cross section, of a preferredembodiment of a governor in accordance with my invention; and

FIG. 2 shows a cross-sectional view of the governor taken along the line2-2 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the embodiment shown in FIGS.1 and 2, l have assumed that my speed limiting device or governor is tobe used with the internal combustion engine of a conventionalautomobile. However, it is to be understood that my governor may be usedwith any type of engine whose speed is to be limited. My governorcomprises a closed, hollow structure that is generally cylindrical inshape. The structure 10 is formed by two substantially similar halvesll, 12 which are formed of metal and provided with respective circularflanges 11a, 12a for joining the two halves 11, 12. A flexible rubberdiaphragm I4 is positioned between the two halves 11, 12, preferablybetween the flanges Illa, 12a so as to be held by the same screws orother fastening elements which are used to join the flanges 11a, 12a.The diaphragm 14 is made from a piece of flexible rubber that isgenerally circular in shape and that is depressed or dished toward thehalf has shown in FIG. I. The half It and the diaphragm 14 are arrangedand constructed so that they form an airtight chamber 15. This airchamber 15 is provided with an air inlet 17 which is arranged to beconnected to a source of air whose pressure varies as a function of thespeed of the engine to be controlled. This air pressure is preferablyarranged to be directly proportional to the engine speed. This source ofair can be provided by any suitable means, such as by an air pumpconnected to the engine distributor, or to the engine crankshaft, or tosome other convenient power takeoff point. The air from this pump orsource is supplied to a suitable hose or pipe 20 which is connected tothe air inlet 17. I prefer that the hose or pipe 20 be provided with anair bleeder valve 21 which can vent any desired amount of air from thehose 20 in order to provide an adjustment for the air pressure suppliedto the air chamber 15.

The half 12 is provided with a central circular opening in which acylindrical bushing 24 is slidably positioned. The bushing 24 isprovided with a cylindrical hole for receiving a link 25. The link 25 isslidably positioned in the bushing 24, and has one end 25a attached tothe face of the diaphragm 14 away from the air chamber IS. The link 25may have a threaded adjustment portion 25b so that the length of thelink 25 may be adjusted. The other end 250 of the link 25 is connectedto a suitable speed control mechanism for the engine. This connection at25c might be a pin and slot arrangement such as shown asfand g ofU.S.Pat. No. 702,090 to Duryea in his FIGS. 1 and 2 so as to give aunidirectional control for governor purposes. This speed controlmechanism may include a butterfly valve 28 which is positioned in theair intake of the engine carburetor. Or, the speed control element maybe some other engine control element, such as the gas feed or theaccelerator pedal.

A helical compression spring 30 is positioned around the link 25 nearits end 25a, between the diaphragm 14 and the bushing 24. Thecompression spring 30 is preferably positioned between two washers 31,32. The washer 32 is urged inward against the compression spring 30 bythe bushing 24. The bushing 24 in turn is urged inward against thewasher 32 by a speed change arm 34. As shown in FIG. 2, the speed changearm 34 has two pieces which pass around the link 25. The speed changearm 34 is pivoted at its lower end 340 on a pivot 35 attached to thehalf 12. The arm 34 is held at its upper end 34b by a pin 36 which canfit in one of a plurality of adjustment holes 39a through 39e. The holes39a through 3% are provided in a bracket 39 which is also attached tothe half 12. The upper end 34b of the speed change arm 34 is shown withits pin 36 positioned in the hole 39d. If the speed change arm 34 ismoved to the left as viewed in FIG. 1 (this being the high speeddirection), the compression spring 30 is compressed. If the speed changearm 34 is moved to the right as viewed in FIG. 1 (this being the lowspeed direction), the compression spring 30 is released to some extent.Thus, the force on the compression spring 30 is fixed in accordance withthe position of the speed change arm 34. However, the link 25 can movein its bushing 24 for any position of the arm 34, so that whensufficient pressure exists in the air chamber 15, the diaphragm 14 willbe flexed or pushed outward against the force of the compression spring30. This motion of the diaphragm 14 also moves the link 25 to the rightas viewed in FIG. ll. This movement of the link 25 can be used to causethe butterfly valve 28 to be closed, thus limiting the speed of theengine or other device. FIG. 2 shows how two pieces of the speed changearm 34 are spaced from the link 25, but press against the bushing 24 soas to position the bushing 24 against the compression spring 30.

It will thus be seen that my invention provides a device which, althoughrelatively simple in construction, provides an effective and reliabledevice for limiting the speed of an engine. My device is powered by airwhich can be supplied under a pressure proportional to engine speed byany suitable means. This permits flexible hose or tubing to be usedbetween the source of air and my governor, so that the governor can bemounted at any desired location on the engine, such as by the bracket40. While my device is relatively simple in operation and construction,it provides an effective speed limiting. And, my device is easy tomount, requires relatively few brackets, and can be positioned close tothe speed control element of the engine. While I have shown only oneembodiment of my device, persons skilled in the art will appreciate thatmodifications may be made. For example, the structure may be made ofother materials and may have other shapes, although I prefer the twometallic halves ll, 12 which are substantially similar. Other means canbe provided for providing the compression force, although I prefer thehelical compression spring 30 which is shown. In addition, the bleedervalve 21 may be omitted if desired. And, the speed adjustment holes maybe omitted, and different sizes of compression springs used instead.Therefore, while my invention has been described with reference to aparticular embodiment, it is to be understood that modifications may bemade without departing from the spirit of the invention or from thescope of the claims.

lclaim:

l. A device for governing the speed of an internal combustion engine foran automobile or the like, comprising:

a. a wall and a flexible diaphragm forming a closed air chamber, saidwall being adapted to be held in a fixed position;

b. an air inlet provided for said air chamber, said air inlet beingadapted to supply air to said air chamber that has a pressure which isdirectly proportional to the speed of the engine to be governed;

. a link connected at one end to said flexible diaphragm and extendingin a direction away from said diaphragm and said air chamber, the otherend of said link being adapted to be connected to a speed control devicewhich controls the air intake through the carburetor of the engine to begoverned;

d. a spring element engaging said flexible diaphragm, said springelement being arranged to urge said diaphragm toward said air chamberwith a selected force so that a selected air pressure indicative ofengine speed is required to overcome the force of said spring element inorder to move said link connected to said flexible diaphragm;

e. a lever support means having a plurality of mounting locationstherein and attached to said device; and

f. a lever pivotably attached at one end to said device and having meansfor selectively attaching its other end to any of said plurality oflocations, an intennediate portion of said lever being connected withsaid spring element whereby the positioning of said other end of saidlever determines said selected force.

2. The device of claim 1, and further comprising an air bleeder valveconnected to said air inlet.

3. A device for limiting the speed of an internal combustion engine foran automobile or the like, comprising:

a. a closed, generally cylindrical, hollow structure formed bysubstantially similar first and second halves joined together;

b. a generally circular, flexible diaphragm positioned between saidfirst and second halves and arranged to form an airtight chamber betweensaid diaphragm and said first half;

c. said first half having an air inlet adapted to be connected to asource of air having a pressure which is directly proportional to thespeed of the engine to be limited; d. said second half having agenerally circular opening therethrough;

e. a cylindrical bushing slidably positioned in said circular opening insaid second half, said bushing having a circular hole therethrough;

f. a link having one end attached to said diaphragm, said link extendingfrom its end of attachment slidably through said bushing hole andterminating at the other end, said other end of said link being adaptedto be connected to an element of the internal combustion engine forlimiting the speed of the internal combustion engine;

g. a compression spring mounted on said link between said diaphragm andsaid bushing;

h. and a lever pivotably attached at one end to said device and havingmeans for selectively attaching its outer end to any of said pluralityof locations, an intermediate portion of said lever being connected withsaid spring element whereby the positioning of said other end of saidlever determines said selected force.

4. The device of claim 3 wherein said means attached to said hollowstructure comprise a speed change arm pivotally attached at one end tosaid second half and extending around said link at the outer face ofsaid bushing to its other end, and adjustable means for fixing theposition of said other end of said speed change arm.

5. The device of claim 3 wherein said link is adjustable in length.

6. The device of claim 5 wherein said means attached to said hollowstructure comprise a speed change arm pivotally attached at one end tosaid second half and extending around said link at the outer face ofsaid bushing to its other end, and adjustable means for fixing theposition of said other end of said speed change arm.

7. The device of claim 6, and further comprising a bleeder valveconnected to said air inlet.

8. The device of claim 6 wherein said speed change arm comprises twopieces which pass around said link, said two pieces being spaced fromsaid link but engaging said outer face of said bushing.

1. A device for governing the speed of an internal combustion engine foran automobile or the like, comprising: a. a wall and a flexiblediaphragm forming a closed air chamber, said wall being adapted to beheld in a fixed position; b. an air inlet provided for said air chamber,said air inlet being adapted to supply air to said air chamber that hasa pressure which is directly proportional to the speed of the engine tobe governed; c. a link connected at one end to said flexible diaphragmand extending in a direction away from said diaphragm and said airchamber, the other end of said link being adapted to be connected to aspeed control device which controls the air intake through thecarburetor of the engine to be governed; d. a spring element engagingsaid flexible diaphragm, said spring element being arranged to urge saiddiaphragm toward said air chamber with a selected force so that aselected air pressure indicative of engine speed is required to overcomethe force of said spring element in order to move said link connectEd tosaid flexible diaphragm; e. a lever support means having a plurality ofmounting locations therein and attached to said device; and f. a leverpivotably attached at one end to said device and having means forselectively attaching its other end to any of said plurality oflocations, an intermediate portion of said lever being connected withsaid spring element whereby the positioning of said other end of saidlever determines said selected force.
 2. The device of claim 1, andfurther comprising an air bleeder valve connected to said air inlet. 3.A device for limiting the speed of an internal combustion engine for anautomobile or the like, comprising: a. a closed, generally cylindrical,hollow structure formed by substantially similar first and second halvesjoined together; b. a generally circular, flexible diaphragm positionedbetween said first and second halves and arranged to form an airtightchamber between said diaphragm and said first half; c. said first halfhaving an air inlet adapted to be connected to a source of air having apressure which is directly proportional to the speed of the engine to belimited; d. said second half having a generally circular openingtherethrough; e. a cylindrical bushing slidably positioned in saidcircular opening in said second half, said bushing having a circularhole therethrough; f. a link having one end attached to said diaphragm,said link extending from its end of attachment slidably through saidbushing hole and terminating at the other end, said other end of saidlink being adapted to be connected to an element of the internalcombustion engine for limiting the speed of the internal combustionengine; g. a compression spring mounted on said link between saiddiaphragm and said bushing; h. and a lever pivotably attached at one endto said device and having means for selectively attaching its outer endto any of said plurality of locations, an intermediate portion of saidlever being connected with said spring element whereby the positioningof said other end of said lever determines said selected force.
 4. Thedevice of claim 3 wherein said means attached to said hollow structurecomprise a speed change arm pivotally attached at one end to said secondhalf and extending around said link at the outer face of said bushing toits other end, and adjustable means for fixing the position of saidother end of said speed change arm.
 5. The device of claim 3 whereinsaid link is adjustable in length.
 6. The device of claim 5 wherein saidmeans attached to said hollow structure comprise a speed change armpivotally attached at one end to said second half and extending aroundsaid link at the outer face of said bushing to its other end, andadjustable means for fixing the position of said other end of said speedchange arm.
 7. The device of claim 6, and further comprising a bleedervalve connected to said air inlet.
 8. The device of claim 6 wherein saidspeed change arm comprises two pieces which pass around said link, saidtwo pieces being spaced from said link but engaging said outer face ofsaid bushing.